In a 3rd Generation Partnership Project (3GPP) that is a standardization project of a mobile communication system, an introduction of a new carrier type (NCT) on and after the release 12 is under review.
As one of NCTs, it is proposed to reduce a cell-specific reference signal (CRS) compared to a legacy carrier type (LCT) (for example, see Non-Patent Literature 1). This makes it possible to use radio resources used for transmission of the CRS for transmission of user data (a data signal) or the like, and thus the throughput can be improved.